Seiko Cal. 3840 - 707

The 3840-707 is a sought-after Spring Drive piece from Seiko's golden era. The Bidirectional bezel and 44mm case give it a distinctive presence on the wrist. [seikata-wm-44f70df7acfb]

Also known as: Sumo

Specifications

Movement

Spring Drive

Case Material

Hardlex-Coated Steel

Case Width

44mm

Case Thickness

9.5mm

Lug Width

19mm

Crystal

Sapphire

Bezel

Bidirectional

Water Resistance

40m

Dial Color

Cream

Jewels

20j

Frequency

28,800 bph

Power Reserve

55 hours

Year

1998

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